I had the harmon in today because I am showing my wife mercy as she has a killer cold/flu. I was noticing the differences in how the instrument played, resonated and moved across partials and the thought occurred to me that I have never ever practiced using a mute. It's always been basically plug and go. The one exception for me was the first time I had to play Lil' Darlin' in high school jazz band for a solo using a harmon. So has anyone ever had a teacher or even on their own worked on playing with a mute just for that purpose?